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Monthly Archives: July 2012

Growing beautiful roses begins with proper rose planting techniques and requires neither great rose gardening skills nor experience. The following information describes how to get your new rose plant off to a great start.

Simply use a little common sense in your choice of location, follow the steps outlined here and voila – your roses are off to a healthy start.

Choose a sunny area of the garden that gets at least 4 to 5 hours of sun. Do not crowd your rose with other trees and plants. Some roses, such as climbers and shrubs, don’t mind company, but most like to mix with other roses or other non-invasive plants. If you’re replacing an older rose bush, it is important to remove an 18 cubic inch area of soil and replace it with fresh soil. A newly planted rose doesn’t like to grow in the same soil that an older rose bush has been in.
Bare Root Roses -An easy and inexpensive option for early season planting. Late winter is the best time plant bare-root roses.

Container Roses – A container rose already has plenty of leaves and maybe some blooms. Early spring is the best time to set out plants grown in nursery containers (vs. bare-root, packaged plants).

Step-by-Step instructions for Planting Roses

1. If you have a bare root plant, soak it in a bucket of water before planting. For roses that are potted, you can water the pot thoroughly and let it sit until ready to plant.

2. Dig a hole approximately 15 inches deep and 18 inches wide. If planting bare root roses, form a small mound of soil in the center of the planting hole. If you live in a colder area, plant a bit deeper and consult with your local garden center.

3. Add a small handful of bonemeal to the planting hole. Spade in some compost or peatmoss to loosen the soil. Mix the soil you took out of the hole with more compost or peat moss.

4. Remove the rose from the pot. Carefully place in the hole and shovel the extra soil around the new plant. Plant the rose with the crown slightly deeper than the original soil. The crown or bud union should be about 1 inch under the soil

5. Gently firm the rose into its new home and water well.

Prune roses in winter or early spring once the rose starts to show signs of new growth, usually in the form of tiny red buds swelling. These buds will become new branches.

Cut out any obviously dead or damaged branches first. Then cut out all but four or five healthy main stems.

Cut the stems back by a third to a half, depending on how tall you want the bush to be. Make these cuts right above an outward-facing bud – that is, a red bud that's on the outside of the rosebush. This directs the bud to grow up and out, leaving the center of the rose bush open for a prettier shape and better air circulation.

Water your roses frequently, but not heavily. Too much water at one time can cause your roses' roots to rot and leaves to mold. Do not use high water pressure when watering your roses or you will wash away soil and valuable nutrients.

Mulch. Roses need less weeding and watering and have fewer diseases if you lay down 1 to 2 inches of organic mulch, such as wood chips, pine needles, grass clippings or other biodegradable material.

Deadhead. This simply means trimming off spent roses to encourage the bush to produce more. While some roses bloom only in one big flush in June, others are bred to keep producing off and on all season long.

Stop fertilizing roses in early autumn, at least one month before your region's first annual frost date. Fertilizing too long into autumn encourages roses to produce tender new growth that will get nipped by cold. Protect roses as needed in late autumn, after your region's first hard freeze

Disease and Insect Pests

Roses are susceptible to a number of disease and insect pests. Roses may survive without a basic pest control program, but they may not be very attractive. A pest control program starts with proper site selection, good soil preparation, good drainage, proper spacing, cultivar selection, and plant maintenance. These all foster healthy roses that are better able to withstand the pressure of disease and insects.

When selecting roses, note the resistance to disease of a particular cultivar or named variety within a class. You want to select by cultivar, not by class. All too often, many gardeners assume that shrub roses (the class) are very tolerant or resistant to disease and make their selection based solely on class. In fact, there are a number of cultivars that are very prone to severe disease injury.

Another interesting fact about diseases is that plants can have two types of resistance: phenotypic or genotypic. Phenotypic resistance is when a cultivar is resistant to a disease in one location or part of the country but not in another. Genotypic resistance is due to the presence of genes that are not affected by climate, location, or horticultural practice. That is why, when the term "resistance" is used as a blanket term and assigned to a variety or class, it may or may not apply depending on where you garden.

Blackspot

This fungal disease can cause almost complete defoliatiation of bushes by early fall, resulting in a weakened bush on which cane die-back and cankers become severe. Blackspot is identified as circular black spots that appear on the upper surface of the leaves, starting at the bottom of the plant and moving upward. Infected leaves turn yellow and fall off prematurely. The fringed margin and black color distinguish this leaf spot from others. Infections on canes are identified as reddish-purple spots. Splashing water spreads blackspot. Infection occurs after leaves are wet for several hours, making it more serious during rainy periods. Some roses are less susceptible than others, so cultivar selection is important. The fungus overwinters in fallen leaves and stem cankers. Raking and removing these leaves as well as pruning out affected canes by spring before the buds swell may help provide some control. Avoid wetting the leaves when watering and locate plants where there is good air circulation. Fungicide spray programs need to be started as soon as new leaves appear in the spring.

Powdery Mildew

Powdery mildew is a fungus disease that affects young leaves, causing them to curl and twist and develop a purple coloration. As the disease progresses, leaves become covered with white powdery fuzz. Whereas blackspot is usually most severe on the lower part of the plant, mildew affects the top part of the plant. Mature leaves are less likely to be affected. Mildew is spread by wind and develops rapidly during periods of warm, dry days followed by cool, humid nights. Infections of mildew are actually discouraged by the presence of water on the leaves. However, keeping plants wet all night to avoid mildew provides an environment that allows other diseases to develop. Infection can be reduced through sanitation and fungicide spray programs. Prune out all dead and diseased canes to reduce initial fungus infection. Because new growth is especially susceptible, thorough coverage of new growth with fungicide is important. Plant roses in areas where they receive good air circulation and where the foliage can dry off rapidly in the early morning to prevent many types of diseases.

Stem Cankers

There are several fungi that cause cankers on roses. The different fungi can cause different-looking cankers, but they usually produce brown, oval-shaped, sunken, or shriveled areas anywhere on the cane. The cane dies, and leaves wilt from that point outward. Sometimes small black specks can be seen on the cane surface within the borders of the canker. These are fungal spore-forming structures. Cankers should be pruned out each year. Make the cut well below the affected tissue. Protect the plant from cold or freeze injury by providing adequate cover over the winter. Do not cover roses too early in the fall. When roses are mulched before the soil freezes, moisture can be trapped around the canes and this can increase the damage caused by canker disease. Keep plants vigorous with proper culture and disease control. Canker is a disease of stress. If plants are kept actively growing, they stand a better chance of avoiding cankers. There are no effective chemical controls for canker disease.

Botrytis Blight

Botrytis blight is a fungal disease that generally attacks dying tissue. It is frequently found on older flowers and other plant parts. Under certain conditions it may also attack healthy tissue. Botrytis favors moist, wet conditions, often causing the disease to attack entire flowers and produce a gray fuzzy mold. This disease is often called gray mold. Good garden sanitation and removing spent flowers often result in good control of this disease. When this is insufficient in providing adequate control, a preventative spray program may be necessary.

Mosaic

Rose mosaic is caused by a virus. Bright yellow patterns made up of wavy lines may appear on the leaves of some varieties. Other varieties may show no yellow lines, but may be stunted and weak due to virus infection. Virus-infected plants cannot be cured. Plant virus-resistant roses if possible. Try to control insects, especially aphids, since they help spread the virus. If you are pruning virus-infected plants, don't prune healthy plants unless you first disinfest your pruners. Dipping the blades in a 10 percent solution of chlorine bleach and water for 60 seconds can do this. A 25 percent concentration reduces the time needed to about 10 seconds. All infected plants should be removed and destroyed to reduce the spread of the virus to other plants.

Crown Gall

Crown gall is a bacterial disease that can survive 15-20 years in the soil. It causes irregularly shaped, rough, dark-colored masses (galls) to appear on stems near the soil line. These galls can appear as small swellings or be several inches in diameter. Severely infected plants become stunted and fail to grow properly. There are no effective controls for crown gall. Severely infected plants should be dug up and discarded and roses should not be planted in that area for at least 5 years. Avoid buying plants with suspicious swellings or gall on lower stems or crowns. However, do not confuse crown gall with normal swellings that you see as a result of the budding process. Protect plants from injury on stems during cultivation. Maintain vigor with fertilization and watering. Crown gall is not specific to roses and can affect apples, raspberries, honeysuckle, euonymus, and many vegetables. For this reason, roses should not be planted where plants susceptible to crown gall have been removed because of the disease. Galltrol-A, a non-pathogenic bacteria, has been used to prevent crown gall. It is often used as a dip on cane root roses prior to planting.

Rose Rosette

Rose rosette is becoming more common and can result in significant damage. This pathogen (not yet positively identified) is spread by an eriophid mite. Symptoms include rapid growth of shoots, development of "witches' broom," development of tufts of small, deformed reddish leaves and excessive thorniness. Plants decline over time. Because affected plants can't be cured, it is best to dig out the affected plant and destroy it. Controlling the mite has been labeled as an option but attempts at controlling it have proven inconclusive. It is very difficult to apply sprays in a timely and satisfactory way.

Aphids

Aphids are very common pests. Aphids are soft-bodied insects that can be red, green, yellow, or black. They feed on very young succulent shoots, causing distortion. Aphids are often kept in check by natural predators. Alternative control measures include the use of insecticidal soaps, strong streams of water to knock them off the plant, or insecticides.

Japanese Beetles

These hard-shelled, metallic-green, black, and gold insects can cause extensive damage to roses just by their sheer numbers and voracious appetite. They prefer flowers and flower buds but will also attack foliage. Japanese beetles are difficult to control because they are strong fliers and constantly reinvade the area. Home gardeners still find that Sevin provides the best control, but it is only topical. This means that reapplication needs to be done on a regular basis to protect the foliage and flowers. Beware of Japanese beetle traps. Traps are almost too effective and will draw a great number of beetles into an area, making the problem worse. If they are used, they should be placed in areas away from the rose garden. Hand picking is also a suggested control for small numbers of beetles.

Leaf Cutter Bees

It is unusual to see the insects at work, but they make their presence known by the perfectly round holes cut near the edges of the leaves. These leaf pieces are used to make egg partitions inside their burrows. The damage they cause is strictly cosmetic and warrants no control.

Spider Mites

Mites are very tiny relatives of spiders. They can be red, black, or brown in color. Mites pierce the underside of rose leaves and suck sap, causing the leaf to turn gray or bronze. A fine web is a sign of a heavy infestation. Mites reproduce rapidly, resulting in high populations in a short time. Mites flourish in crowded, stagnant gardens. A high-pressure washing with water from a garden hose directed to the underside of the leaves every 2-3 days can manage mites. This will interrupt their life cycle. Miticides such as dicofol help in heavy infestations. Insecticidal soaps are also effective in controlling mites.

Thrips

Thrips are extremely small, brown insects usually living and feeding inside of the blooms. A deformed flower with flecked or scratched petals is usually a sign of a thrips problem. The rasping mouth parts of thrips causes this injury when they scratch the petal surface to feed. Thrips are especially attracted to yellow or light-colored roses. Some control can be achieved using materials such as orthene, malathion, or insecticidal soap, but even these often give poor results. They tend to be worse during late June, July and August when temperatures are warm.

Rose Midge

The rose midge is a tiny fly that lays eggs in the buds and shoots of roses. The larvae that develop start feeding and causes bent, mishapen or blasted flower buds and withering of the stem tips. Eventually they turn black. Control consists of pruning out buds and applying insecticide if the problem persists. Midge damage usually shows up in July. Because the larvae fall to the soil to pupate, an effective control is to place weed barrier fabric under the plants to catch the larvae and prevent them from entering the soil to pupate.

Sawfly (Rose Slug)

The common rose slug causes skeletonizing or window pane like damage to rose leaves in spring and early summer. The larvae look like caterpillars but are actually more closely related to bees and wasps. Common rose slugs are green with a light tan head and often have may hairlike bristles. Although they look like caterpillars, products with a BT are not effective because they are not larvae of moths or butterflies. Control can include hand picking and the use of horticultural oils or insecticidal soaps.

Fungicide Spray Programs

Fungicides generally recommended for blackspot control include:

Daconil 2787 or fungicides containing Daconil

Phyton 27

Mancozeb

Funginex

Orthenex.

Frequently used fungicides for control of powdery mildew include:

Captan

Daconil 2787

Phyton 27

Funginex

Orthenex

Materials used in limiting botrytis are:

· Captan

· Daconil 278

· Mancozeb

As with all spray materials, follow label directions carefully for mixing and applying.

A cicada killer is a wasp and its body is large compared to the usual wasp. It needs to be bigger to match the size of its prey, the cicada (sometimes call locust). The female at 1 1/2 inches is nearly twice as large as the male. The males only job is to find a female and mate, tough work. The female takes care of the reproduction, slays the prey, builds the home, feeds the young, defends the home, and then closes the door. The male emerges from the ground mid July when it senses the buzzing sound of the cicadas above ground. The female digs her way out of the ground about 2 weeks later. While the male waits for the female, he scouts out an area where he suspects a large number of females will be underground. When the males territory is threatened by other intruding males and maybe even big objects, like people, he will fly around making a lot of buzzing noise discouraging would be competitors from claiming his space. He has a small false stinger that cannot penetrate human skin. He has no defensive instinct to sting but sure can intimidate.

The female comes up from her burrow and mates once with the male who claimed the area. Now she has to dig a new burrow in which to lay her eggs. This burrow or hole may be several feet deep and have multiple branches and cells. It is big enough around that a persons thumb can fit into it. There will be a sizable amount of dirt piled to the side of the hole from her excavation. If the female cicada killer is in the hole and disturbed by noises and footsteps above ground she will stay in the hole and loudly buzz hoping to scare the invader. She will fly around and around the area orienting herself to the burrows position. She has to remember where each burrow is placed in order to bring the hunted prey back. Her flight and loud buzzing sounds are unsettling to us folks even scaring the big dogs, not to speak of the the children.

The female cicada killer now goes on the hunt for a cicada. She will need one cicada for each cell. The cicada is stung, paralyzed but alive to be drugged down to the cell. The egg is laid and in just days will hatch into a larva to feed on the cicada. An amazing fact is that the cicada will live twice as long as a cicada not stung and paralyzed. To our thinking, that is not a good thing! If the egg to be laid is a male she will lay one male in each cell but if it is a female she will place two female eggs per cell. The larva eats the cicada within 2 weeks and then grows into a prepupal stage to overwinter.

The female cicada killer lives about 30 days total. In that time she builds her babies a home, provides for their meals and secures their safety, what a good mom, all the while without stinging anyone of us. She can but the stinging sensation is so slight that on a scale of insect bite pain of 1 (being the lowest) and 5 (being the worse to make an adult cry) her sting is rated point five, .5. Her stinger is short and not too hard. The venom rarely causes an allergic reaction. She would attempt to sting if trapped in your hand or in some way physically threatened. Leave her alone and she leaves you alone. There are chemical controls of the cicada killer. The preyed upon cicada damages tree limbs by making a slit in the tender bark of a young limb and depositing eggs underneath. This slit can provide opportunities for disease and insect damage to the open wound later in the season. Compare that to the annoying sounds of loud buzzing of the cicada killer which does not harm a tree in any way nor does it intentionally harm people. Which is the lessor evil. If you elect the cicada killer because it sounds and looks threatening and choose to chemical treat them as the problem you should evaluate the cost and harmful circumstances to yourself and the environment. Your problem naturally goes away in about 6 six weeks anyway, all on its own. The cicada killer does what nature intends – control the population of another insect injurious to trees. If we reduce the number of cicada killers we are unintentionally increasing the number of cicadas. A chemical control is not as easy as driving to the store, putting down the bucks, and applying the chemical to a hole in the ground. Your efforts are not guaranteed and neither is your safety. There are reliable chemical controls available to the homeowner. Please read the entire label, apply as directed, and adhere to safety requirements. Call your county Extension office for chemical names and additional information.

Saturday, July 28th, the Jubilee Prairie Dawgs will host a guided tour of restored prairie in the far North of Jubilee State Park.

Entomologists from the Peoria Academy of Science will reveal the importance of prairie insects. Expect to see familiar and unfamiliar prairie plants in full bloom as well as visiting butterflies. Dress for walking in long grass. Insect repellant provided.

Meet at 9 a.m. at the barn at the top of the gravel driveway next to the Peoria Astronomy Society observatory on Brimfield-Jubilee Road.

Directions: From Kickapoo, go west 0.8 mile on US150; then 3.7 miles north on Princeville-Jubilee Road (R40); then 2.5 miles west on Brimfield-Jubilee Road (D29). Look for our small Prairie Dawg signs starting at Brimfield-Jubilee Road. If you have any questions or would like a map, contact Doug Franks: doug.franks@comcast.net or phone 309-691-7993 or cell phone 309-868-9180.

HISTORY OF THE DAWGS

The Jubilee Prairie Dawgs is a hands-on volunteer group dedicated to conserving prairie.

In 1978 Hal Gardner and some Sierra Club friends, calling themselves the Jubilee Prairie Dawgs, started clearing brush on prairie remnants in Jubilee State Park. The Prairie Dawgs have worked continuously since, expanding these remnants and improving their quality through weeding, brush cutting, seed collecting, planting from pots, and burning.

I am amazed by plants that can grow in very hot, dry conditions. In fact, certain plants seem to thrive in the hot, dry weather. Since I garden in the even drier sands of Mason County, I have tried to use drought tolerant plants, whenever possible. Here are some plants that have worked well for me over the years.

marigold, zinnia, and vinca

The old standard annuals seem to do best for me in drought years. These include nicotiana, celosia, marigold, zinnia, and petunia. We water these plants a couple times a week and they do fine, considering the conditions.

Nicotiana is also called flowering tobacco. It is easy to grow and especially valuable for hot, humid areas. Plants are seven to ten inches tall. Flowers are one to two inches across with five distinctive petals. ‘Avalon Bright Pink’ was an award winner in 2001 and the nightly aromatic variety ‘Perfume Deep Purple’ won in 2006.

Celosia are also heat and drought tolerant. I’ve grown both the plume and crested types. Celosia are so drought tolerant that they rot is the plant is too wet (or too cold). I have to plant these in an

unirrigated area.

Marigold and zinnia grow in all types of situations, as long as there is full sun. I particularly like the Profusion zinnias, especially the Fire and Orange varieties.

Although most of my yard has in ground irrigation, my perennial bed is not uniformly watering. The plants doing well there include black-eyed Susan, purple coneflower, yarrow, and sedum. This makes a lot of

sense since these are native plants that do well in our dry prairie conditions.

double coneflower

I have been particularly impressed with a new variety of purple coneflower that I added this year. Each of the double, pompom-like flowers are sturdy and last for several weeks.

I can also see a difference in the shrubs in my yard, particularly those where the irrigation heads don’t reach. The burning bush doesn’t like the hot, dry weather and so I have had to give them additional water. I also have several lilacs that are drying up. My red twigged dogwoods develop yellow leaves very quickly if not watered almost every day. And, my new hydrangea collection must have extra water to prevent daily wilting.

Hopefully, you have some plants in your yard that look good in this year of extremes. Keep watering your plants, remembering that thorough deep watering is better than daily sprinkles. Don’t forget the established trees, especially evergreens that will need water going into the fall to assure that they don’t have major winter injury.

Tomatoes are one of the most popular vegetables planted by home gardeners. They do have a few problems and this year, along with the drought, may have one or more of these difficulties. Here are some of the problems that gardeners may be seeing according to Jim Schmidt Horticulture Extension Specialist.

Flower Drop. Tomatoes do not set fruit when day temperatures are above 95°F., especially with hot, dry winds. Night temperatures above 70° also can reduce fruit set. The recent blast of hot weather most likely put tomato plants into a holding pattern. My plants, which are supposed to have clusters of small tomatoes, show two or three tomatoes forming and the other stems have dried flowers. Jim says to continue to water and feed and mulch if possible and tomatoes will come along later.

Blossom-end Rot. This disorder appears as a dry, sunken, leathery rot on the bottom, or blossom end of the tomato fruit. The Master Gardener Helpline gets many calls about this problem but usually it appears on early maturing fruits, but tomatoes which ripen later are OK. It is actually caused by a calcium deficiency provoked by lack of available moisture. Plants that are pruned (as in removing the suckers on staked tomatoes) have increased susceptibility to this condition as well as those where someone weeded around the plants too deeply, cutting off roots which restricts water uptake. It usually happens during prolonged dry periods that occur while the plant is making vigorous growth. The best way to prevent blossom-end rot is to provide uniform water to the plants once a week (twice a week during extremely hot weather) with 1 inch of water and place a 2 to 4-inch mulch around the plants to retain moisture. If you are staking or caging the plants, avoid pruning severely.

Cracking. Irregular watering (or sudden summer rains) after a dry period may cause fruit cracking. The cracks are generally located around the sides of the fruit. The tomatoes are still useable. Gardeners should water on a regular schedule when rainfall is lacking and use mulch to retain moisture in the soil. Certain varieties seem to be prone to cracking.

Foliage Diseases, the blights, the spots and the wilts.
Early blight (Alternaria solani). This disease occurs on the leaves, stems, and fruits, though it is most noticeable on the lower leaves of the plant. Look for small, dark brown spots with concentric rings. Similar spots may appear on the stems. Spots on the fruits will be dark, sunken, and leathery. The disease is favored by humid weather and temperatures above 75°F. To control this disease, provide ample spacing around plants for good air circulation. Avoid watering the plants late in the day, and keep water off the foliage by watering near the base of the plants. Regular application of fungicide sprays can be used for control. At the end of the season, be sure to rake up all plant residue and plan on rotating the tomato planting to a different area next year.
Late Blight (Phytophthora infestans). Tends to be more serious with cool, wet weather. Leaves infected with this disease first develop greenish-brown or black water-soaked spots starting at the tip with a white, downy mold appearing along the margins of the infected area and on the undersides of the leaves. Controls are same as Early blight.
Septoria Leaf Spot (Septoria lycopersici). This is a serious disease on the foliage. Infected leaves develop circular water-soaked spots that have gray centers and blackish borders. Tiny dark specks develop in the centers of the spots. If spotting is severe, the leaves eventually die and fall, and fruits are subject to sunscald.
Fusarium Wilt (Fusarium oxysporum). This is a soil disease that causes rapid wilting of the plants. Symptoms include a yellowing, wilting, and dying of the leaves progressing from the bottom of the plant upward. This usually happens about the time of fruit set but may occur any time during the growing season. The disease is most active during warm weather when soil temperatures are between 75 and 85°F. It can be prevented by growing resistant varieties but many old-time favorites lack resistance. Infected plants should be removed immediately. Gardeners should choose resistant varieties when selecting plants in the spring and rotate to another garden location next year.
Verticillium wilt (Verticillium sp.). A soil fungus with symptoms similar to Fusarium wilt, though it tends to be more serious with cooler weather. The leaves wilt, gradually wither, die and drop off. Eventually only the tip leaves appear green and alive, and the fruit may be small. Defoliation exposes the fruit to sunscald. As with Fusarium wilt, selecting resistant varieties and planting in a different location the next year are recommended practices.

In spite of the possibility of these problems, nothing tastes as good as a big heavy, juicy freshly picked tomato. Plant them, water them, mulch them and eat them. Choose varieties that are labeled resistant to the above diseases and rotate their position in the garden each year.You can avoid some of the problems.